docs: def delete(self, *args):
          """Remove the currently selected item from my store"""
          key = self.name_wid.text or self.name_wid.hint_text
          if not hasattr(self.store, key):
              # TODO feedback about missing key
              return
          delattr(self.store, key)
          try:
              return min(kee for kee in dir(self.store) if kee > key)
          except ValueError:
              return '+'